Doctor’s Note – Week 13

Last week saw the release of Puzzlecraft: The Ultimate Guide on How to Construct Every Kind of Puzzle, a really incredible project with Mike Selinker that was an extension of our GAMES Magazine articles that have run for many years (I joined Mike around article #48 when he wanted to write on how to construct Battleships. I’ve been part of the process ever since as we now approach #100). The title seems overly broad, but I challenge anyone to come up with a puzzle style that isn’t covered in the book.

Last week also saw Mike and I finish construction on a book you’ll get to see next year, Tile Crosswords, a word puzzle style that we developed out of the logic puzzle “Crack-It-On” that first appeared at the WPC in Hungary in the late 90s. You might not picture me as someone who fills grids with letters that have a meaning when considered as intact strings, let alone then provides sets of letters outside the grid that also form strings that evoke the sets of letters that are in the grid — certainly if I write about making word grids and cluing them that way it would seem impossible that I even speak English — but it is something I’ve been increasingly finding joy in doing.

The reason I mention all this is to give you some forewarning that over the coming months we may have other puzzle types than just sudoku and abstract logic puzzles here. Just as with the Hidden Contest that ended last week, I intend Grandmaster Puzzles to have all the kinds of puzzles I would like to solve, but with a friendly mix of easy to hard and lots of different genres so that if today is not your cup of tea, then tomorrow probably is. You may only think of me as a logic puzzle constructor, but working with Mike over the last few years has really developed my puzzle-making chops in almost every area.

Whatever puzzles we release here, they should still be worthy in their genres of being called masterpieces.

Sincerely,
Dr. S

Ask Dr. Sudoku #12 – The line must be drawn here

To [guess], or not to [guess], that is the question:

Whether ’tis Nobler in the mind to suffer

The [Twists] and [the Turns] of outrageous [Logic],

Or to take Arms against a Sea of troubles,

And by [guessing] end them….

We’ve had a fair number of lively discussions in the last week, and if nothing else has come out of them at least the comment threading on the site is now noticeably improved. One question that has come up a lot has been around which puzzles need guesswork, here and elsewhere. A lot of solvers, for the sake of speed perhaps, will say they “had to bifurcate” during a solve here, but that has never been required for our puzzles. This week I wanted to (briefly) state my opinions on what I consider to be “logical” puzzles, since I mention frequently that all puzzles will have a single solution that can be reached by logic alone and it is worth contributors and solvers knowing what I mean by that.

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Dr. Sudoku Prescribes #67 – Sudoku

Sudoku by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Logical solving theme

Rules: Standard Sudoku rules.

Answer String: Enter the 5th row from left to right, followed by a comma, followed by the 6th column from top to bottom.

Time Standards (highlight to view): Grandmaster = 6:30, Master = 10:30, Expert = 21:00

Solution: PDF

Note: Follow this link for other classic Sudoku. If you are new to this puzzle type, here are our easiest Sudoku to get started on. More classic Sudoku puzzles can be found in The Art of Sudoku, The Art of Sudoku 2 and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

Dr. Sudoku Prescribes #66 – Tapa (Pentomino)

Tapa by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to shift between shading mode and the composite Yajilin mode where left click marks cells, right click marks dots in cells or X’s on edges, left click+drag draws lines.)

This is a “Franken-Friday” puzzle variation.

Theme: Pentapa

Rules: Standard Tapa rules. Also, the Tapa wall in this puzzle is made using one of each pentomino given below the grid with no overlaps. Rotations and reflections are allowed. (Note: There is no P pentomino here because it would violate Tapa rules).

Answer String: Enter the length in cells of each of the shaded segments from left to right for the marked rows, starting at the top. Separate each row’s entry from the next with a comma.

Time Standards (highlight to view): Grandmaster = 6:30, Master = 11:00, Expert = 22:00

Solution: PDF

From the Foxger’s Den #10: Fillomino

Fillomino by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between a composite mode for line/edge drawing and a number entry mode.)

Theme: Parquet

Rules: Standard Fillomino rules.

Answer String: For each cell in the marked rows/columns, enter the area of the polyomino it belongs to. Start with the 5th column, followed by a comma, followed by the 7th column.

Time Standards (highlight to view): Grandmaster = 1:30, Master = 2:00, Expert = 4:00

Solution: PDF

Note: Follow this link for other classic Fillomino and this link for more variations on Fillomino puzzles. If you are new to this puzzle type, here are our easiest Fillomino puzzles to get started on.

Dr. Sudoku Prescribes #65 – Star Battle

Star Battle by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Broken Window

Rules: Standard Star Battle rules. Two stars per row, column, and region.

Answer String: For each row from top to bottom, enter the number of the first column from the left where a star appears. Enter these numbers as a single string with no separators.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:00, Expert = 10:00

Solution: PDF

Note: Follow this link for other classic Star Battles and this link for Star Battle variations. If you are new to this puzzle type, here are our easiest Star Battles to get started on. More Star Battle puzzles can be found in The Art of Puzzles, in the book Star Battle by JinHoo Ahn, and in our beginner-friendly collection Intro to GMPuzzles by Serkan Yürekli.

From the Foxger’s Den #9: Slitherlink (Domino)

Slitherlink by Grant Fikes

PDF

or solve online (using our beta test of Penpa-Edit tools; use tab to alternate between edgex mode where left click+drag draws lines and right click marks X’s and a line drawing mode to mark the dominoes.)

This is a “Twisted Tuesday” puzzle variation.

Theme: Double Domino – both domino-based clue groupings, and a domino-based loop.

Rules: Standard Slitherlink rules; also, the interior of the loop must be divisible into dominoes (1×2 rectangles) in at least one way without any overlaps.

Answer String: Enter the length in cells of each of the internal loop segments from left to right for the marked rows, starting at the top. Separate each row’s entry with a comma.

Time Standards (highlight to view): Grandmaster = 4:30, Master = 7:00, Expert = 14:00

Editorial Note: This puzzle is a fair bit more difficult than our usual Tuesday puzzles, but this may be a side effect of the new Twisted Tuesday format.

Solution: PDF

Dr. Sudoku Prescribes #64 – Tourney TomTom

TomTom by Thomas Snyder

PDF

or solve online (using our beta test of Penpa-Edit tools)

Theme: Bracket Buster. Our 64th prescription is the perfect cure for anyone concerned with their logical decision making after the last 48(+4*) basketball games.

Rules: Standard TomTom rules, including the possibility for multi-cell subtraction or division by starting from the largest number.

Answer String: Enter the 2nd row from left to right, followed by a comma, followed by the 3rd row from left to right.

Time Standards (highlight to view): Grandmaster = 1:15, Master = 1:45, Expert = 3:30

Solution: PDF

*Editorial Note: That the NCAA basketball tournament now starts with 68 teams is an accident of greed that I try not to think about too much. Like those two unclued cells in this grid that just don’t seem to fit in completely.

Sunday Surprise #1 – Contest Submissions

In addition to FoxFireX’s incredible sudoku gift that he made for someone’s birthday (some puzzles are meant to keep more private), we got three other submissions for our first Hidden Contest. We’re posting them here in increasing order of difficulty.

First up is an “Anti-Symmetry” Nurikabe from Giovanni P. where every clue that is odd/even has an even/odd clue in the corresponding symmetric place. Standard Nurikabe rules are all you need for this challenge.

Nurikabe by Giovanni P.

Solution image

 

Next up is a real RARITY for this website, a Shakashaka. For the general rules, we’ll direct you to Nikoli.com where the puzzle originated. Here, Bryce Herdt has made a cipher version of the puzzle. The letters AIRTY each stand for a different number from 0 – 4 which the solver must determine.

Cipher Shakashaka by Bryce Herdt

Solution image

 

Finally, the hardest of the bunch, is an intriguing variation called “Sudoku Slitherlink” by its designer Scott Handelman. In addition to standard Slitherlink rules, a different number from 0-3 must go into each green cell. No number in a green cell can repeat in that row or column. As Scott warns, this is one of the hardest puzzles he’s constructed and, from his original post, he’s “still kinda shocked that the middle just kinda ‘works'”.

Sudoku Slitherlink by Scott Handelman

Solution image

 

All of these puzzles are grouped in this single PDF.

If you enjoy these puzzles, please comment here and say so, thanking each of the authors. As contest entries, these didn’t go through editorial review (except making sure there was a single answer), but we found them all quite interesting and worthy of being some of the first puzzles from other authors to appear on this web-site. We’re considering keeping Sunday open for “guest” submissions each week from new puzzle authors. And once we get through a stack of puzzle submissions for The Art of Puzzles, more authors will be appearing throughout the week too.

Ask Dr. Sudoku #11 – About that hidden contest…?

For the last couple weeks Sunday has been a day where we’ve seen a huge increase in page views, strictly because a new hint was released for the site’s first Hidden Contest. This led a few dedicated solvers to scour the site again looking for something out of place.

This Hidden Contest was an experiment in having “other” puzzle styles here; I’m a huge fan of puzzle hunts and secret codes and the like and was curious to see if my more observant solvers would catch onto something odd.

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